Design of functional hydrogels using smart polymer based on elastin-like polypeptides

Elastin-like polypeptides (ELPs) are genetically encoded materials that enable the bottom-up design and manufacture of functional biomaterials. Here, we report the design and synthesis of a lysine-rich ELPs modified with methacrylate groups, giving rise to temperature-induced phase transition and photo-crosslinking capabilities. The degree of methacrylate functionalization could be varied by changing the reactant ratio of N-succinimidyl methacrylate (NHS-MA) to ELPs. The prediction of the structural transition with increasing temperature was validated using integrated experimental and simulation approaches. Combined with hydrogel fabrication strategy, methacrylated ELPs (ELP-MA) can be engineered into different physical forms like coacervates and hydrogels, which further function as light transmittance regulator and elastic adhesives. In addition, physical properties of the hydrogels such as mechanical strength, pore size, and swelling ratio could be controlled by the methacrylation degree and ELP-MA concentration. Subcutaneous implantation in mice showed that the resulting ELP-MA hydrogels exhibited a good biocompatibility. Our biological and chemical engineering approaches to creat functional materials of the ELP-MA will be useful to design various smart materials in the future.

Automated summary

In this study, we designed and synthesized genetically encoded materials called elastin-like polypeptides (ELPs) that can undergo temperature-induced phase transition and photo-crosslinking due to modification with methacrylate groups. The degree of methacrylate functionalization can be controlled by adjusting the reactant ratio. By combining hydrogel fabrication strategy, the methacrylated ELPs (ELP-MA) can be engineered into different physical forms such as coacervates and hydrogels, functioning as light transmittance regulators and elastic adhesives. The physical properties of the hydrogels can be controlled by the degree of methacrylation and ELP-MA concentration. The resulting ELP-MA hydrogels showed good biocompatibility when implanted subcutaneously in mice.